滴灌条件下苜蓿刈割适期的研究

试验以‘新牧4号’紫花苜蓿为材料,研究高频次滴灌条件下不同时期刈割对苜蓿生长及产量和品质的影响,以期为苜蓿生产提供依据。结果表明:不同灌水频次对苜蓿的物候期有影响,高频次的灌溉处理(8 d/次)物候期比低频次灌溉处理(15 d/次)延后2~3天;进入花期以后,苜蓿株高增长速度减缓;随着苜蓿刈割时间的推迟,各处理茎叶比呈增加的趋势,初花期和盛花期刈割处理茎叶比分别达到2.67和2.81,与其他各处理差异极显著(P0.01);初花期刈割可以得到最大的苜蓿干草产量(18220.5 kg/hm~2),但牧草品质较蕾期有所下降;现蕾期刈割的处理粗蛋白产量最高(3702.2 kg/hm~2),干草产量为17563.5 kg/hm~2。

The Optimum Period of Alfalfa Cutting under Drip Irrigation

Medicago Sativa L.cv. Xinmu No.4 was taken as the experiment material to study the effect of cutting time on growth and yield and quality of Alfalfa under frequent drip irrigation, in order to provide basic data for alfalfa production. The results showed that different irrigation frequency had influence on the phenophase of Alfalfa. The phenophase with high-frequent irrigation (8 d/time) was delayed 2-3 d, compared with the low-frequent irrigation (15 d/time). At the flowering stage, the growth of plant height was slowed down. With cutting time delaying, the ratio of stem to leaf of different treatments showed an increasing trend. The ratio of stem to leaf in initial bloom stage and full-bloom stage with cutting treatment was 2.67 and 2.81, respectively, which had significant differences with other treatments (P <0.01). The initial bloom stage with cutting could get the maximum yield of alfalfa hay (18220.5 kg/hm2), but the forage quality declined compared with that in the bud stage. The yield of crude protein was the highest in budding stage with cutting (3702.2 kg/hm2), and the hay yield was 17563.5 kg/hm2.